Abstract
A simple, quantitative density separation method is described. The method is based on differences in specific weight between meiobenthos and sediment. Nematodes and copepods could be separated from sediment and detritus when samples were suspended in Ludox-TM, a colloidal silica. Organisms float at the surface, while sediment particles sink. Results obtained with this new method were compared with the well-known decantation method. For a quantitative isolation of nematodes from sediments, rich in coarse detritus, a maximum volume of 7 cm3 sample could be used. For copepods this maximum was 13 cm3. For such sediments the density method is more reliable than the decantation method. The time needed for sorting the meiobenthic organisms is reduced to about 30% compared with the former method. The new method can be used for preserved as well as for fresh sediment samples and can also be applied for the disolation of small polychaetes, small oligochaetes, larvae of some macrofaunal groups and net-zooplankton.
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Bowen, R.A., J.M.St. Onge, J.B. Colton, Jr. and C.A. Price. Density-gradient centrifugation as an aid to sorting planktonic organisms. I. Gradient materials. Mar. Biol. 14, 242–247 (1972)
Du Pont: Ludox colloidal silica, Product Information Bulletin, 20 pp. E.I. Du Pont de Nemours & Co. (Inc.), Industrial Chemicals Department, Wilmington, Delaware, USA 1973
Heip, C., N. Smol and W. Hautekiet: A rapid method of extracting meiobenthic nematodes and copepods from mud and detritus. Mar. Biol. 28, 79–81 (1974)
Jenkins, W.R.: A rapid centrifugal-flotation technique for separating nematodes from soil. Pl. Dis. Reptr 48, p. 692 (1964)
Uhlig, G., H. Thiel and J. S. Gray: The quantitative separation of meiofauna. A comparison of methods. Helgoländer wiss. Meeresunters. 25, 173–195 (1973)
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Communicated by O. Kinne, Hamburg
Publication No. 10 of the project “Biological Research in the Ems-Dollard Estuary”.
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de Jonge, V.N., Bouwman, L.A. A simple density separation technique for quantitative isolation of meiobenthos using the colloidal silica Ludox-TM. Mar. Biol. 42, 143–148 (1977). https://doi.org/10.1007/BF00391564
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DOI: https://doi.org/10.1007/BF00391564